In order to form an exterior wall of a house, a method in which exterior panels made of a ceramic material, such as cement, are arranged and fixed has been widely used. On a surface of such an exterior panel, a surface pattern is formed to look like many materials, such as a stone, a brick, a tile, and so on. And, in order to form an outward appearance of a house according to the surface pattern of the exterior panel, the exterior panels having the same surface pattern of one kind are arranged on the wall, or the exterior panels having different surface patterns of two or more kinds are combined and arranged on the wall. For example, by using an exterior panel having a concave groove running an entire length of the panel in the longitudinal direction of the exterior panel, it is possible to form an exterior-wall surface in which concave grooves are disposed in a stripe state (see, Japanese Patent Application Laid-Open No. 6-264586).
However, when the exterior panels having the same surface pattern of one kind are arranged on the wall, the same surface pattern is repeated on the whole wall surface, whereby the outward appearance of the exterior wall becomes monotonous. And, when the exterior panels having different surface patterns of two or more kinds are combined and arranged on the wall, it is difficult to give sensation of unity of the outward appearance in the whole exterior wall, and it is likely to become a messy outward appearance.